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52/100

✓ Peer-reviewed alzhub usefulness score 52 out of 100. Risk factors

Topic: Risk, prevention and care in population studies

Of 4930 participants, 2052 (41%) had MCI. Excessive daytime napping and nighttime sleep were associated with worse cognition and cognitive decline. Excessive napping and nighttime sleep were also linked to higher dementia risk (hazard ratios: 1.75 and 1.86, respectively). These findings suggest that excessive sleep in MCI is associated with further cognitive decline and dementia. Highlights: Excessive daytime napping and nighttime sleep are linked cognitive decline for those with MCI.Excessive sleep during the day or at night heighten dementia risk.Worse test scores across multiple cognitive domains were observed for excessive daytime nappers.Excessive sleep in MCI may be a warning sign for further cognitive decline.

Cite this study APA, Vancouver, BibTeX · download .bib or .ris

APA 7th

Overton, M., Sindi, S., Basna, R., & Elmståhl, S. (2025). Excessive sleep is associated with worse cognition, cognitive decline, and dementia in mild cognitive impairment. Alzheimer s & Dementia Diagnosis Assessment & Disease Monitoring. https://doi.org/10.1002/dad2.70093

Vancouver

Overton M, Sindi S, Basna R, Elmståhl S. Excessive sleep is associated with worse cognition, cognitive decline, and dementia in mild cognitive impairment. Alzheimer s & Dementia Diagnosis Assessment & Disease Monitoring. 2025. doi:10.1002/dad2.70093. PMID: 39996036.

BibTeX

@article{overton2025-39996036,
  author  = {Overton, Marieclaire and Sindi, Shireen and Basna, Rani and Elmståhl, Sölve},
  title   = {{Excessive sleep is associated with worse cognition, cognitive decline, and dementia in mild cognitive impairment}},
  journal = {Alzheimer s \& Dementia Diagnosis Assessment \& Disease Monitoring},
  year    = {2025},
  doi     = {10.1002/dad2.70093},
  pmid    = {39996036},
  url     = {https://doi.org/10.1002/dad2.70093}
}

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Key findings

Of 4930 participants, 2052 (41%) had MCI.
Excessive daytime napping and nighttime sleep were associated with worse cognition and cognitive decline.
Excessive napping and nighttime sleep were also linked to higher dementia risk (hazard ratios: 1.75 and 1.86, respectively).
These findings suggest that excessive sleep in MCI is associated with further cognitive decline and dementia.
Highlights: Excessive daytime napping and nighttime sleep are linked cognitive decline for those with MCI.Excessive sleep during the day or at night heighten dementia risk.Worse test scores across multiple cognitive domains were observed for excessive daytime nappers.Excessive sleep in MCI may be a warning sign for further cognitive decline.

Why it matters

Among participants with mild cognitive impairment, excessive daytime napping and nighttime sleep were linked to worse cognition, cognitive decline and higher dementia risk. These findings suggest excessive sleep may be a warning sign, but they do not show that changing sleep habits prevents dementia.

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Study details

Study designcross-sectional
Participants4,930
Evidence strengthModerate

How this study scored 52/100

Published in a peer-reviewed journal, and it is a snapshot of people at one point in time. Scored zero for effect reported and randomised / blinded because the record does not state it.

Component	Points	Why
Journal tier	7 / 10	Tier 3 — peer-reviewed journal (Alzheimer s & Dementia Diagnosis Assessment & Disease Monitoring)
Journal's citation record	1 / 4	Alzheimer s & Dementia Diagnosis Assessment & Disease Monitoring: journal h-index 86 (OpenAlex, 2026-10-29)
Study design	4 / 12	A snapshot of people at one point in time
Strength of evidence	3 / 5	Rated “moderate” in our summary
Peer-review validation	10 / 10	Peer-reviewed. Published as an article in a named peer-reviewed journal.
How recent	4 / 5	2025 — within 3 year(s) of the newest study here
Sample size	3 / 4	4,930 participants
Effect reported	0 / 3	No effect size reported — scores zero (not stated in the record — scored 0)
Studied in people	3 / 3	Studied in people (participant count stated)
Randomised / blinded	0 / 2	No randomisation or blinding stated — scores zero (not stated in the record — scored 0)
Times cited	1 / 7	Cited 4 times (OpenAlex, 2026-10-10)
Citations per year	1 / 5	1.3 citations a year over 3 year(s) since 2025
Impact for its field and year	2 / 6	Cited 2.5× the average for papers of its field and year (OpenAlex FWCI)
Cited by studies here	1 / 6	Cited by 1 other studies in this library
Still being cited	1 / 4	Cited 4 times in 2024–2026 (2026 still in progress; OpenAlex)
Senior author's track record	3 / 4	Last-listed author Sölve Elmståhl: h-index 54 (OpenAlex, whole career)
Institution's track record	2 / 3	Imperial College London: institution h-index 1,744 (OpenAlex)
Multi-centre collaboration	2 / 3	OpenAlex lists 5 institution(s) in 2 countries
Indexed in PubMed	2 / 2	Indexed in PubMed (PMID 39996036)
Free to read	2 / 2	Free to read
Total	52 / 100	—

What each of these 20 components measures, and what this score is not →

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